1. Field of the Invention
The present invention relates to a tape loading device suitable for use in VTRs (Video Tape Recorders), and more particularly, to a tape loading device designed to load a tape in a predetermined running path by the movement of a loading post which is achieved by the rotation of a loading ring.
2. Description of the Related Art
A tape loading device for use in conventional VTRs has the structure shown in, for example, FIG. 1. That is, first and second loading rings 71 and 72 are mounted on a drum base 73 on which a rotary head drum 20 is mounted. A post base 74 (on which a loading post 74a is mounted) is moved to a predetermined position along a guide member 77 by the rotation of the first ring 71 while post bases 75 and 76 (with loading posts 75a and 76a respectively mounted thereon) are moved to predetermined positions along a guide member 78 by the rotation of the second ring 72, whereby a tape 21 is pulled out from a tape cassette (not shown) and is then loaded in a predetermined running path including the peripheral surface of the rotary head drum 20.
Also, the drum base 73 has three shafts 70 planted on the lower portion thereof. Three rollers 79a through 79c and three rollers 79d through 79f rotatably supported on the shafts 70 retain the inner peripheral surfaces of the first and second rings 71 and 72 and thereby rotatably support the first and second rings 71 and 72 on the drum base 73.
Even if the rings 71 and 72 are disposed on a chassis on which the drum base is mounted (alternately, on a chassis formed integrally with the drum base) and are substantially rotatably mounted on the drum base, the same rollers and shafts as those described above are used.
However, in the aforementioned conventional loading device, rotatable retention of the ring 71 (72) requires at least the three rollers 79a through 79c (79d through 79f), three shafts 70 for rotatably supporting the rollers 79a through 79c (79d through 79f), and fixing members, such as mold washers and screws. Thus, the number of parts required is greatly increased, increasing the cost of the VTR.
Furthermore, the increased number of parts and the mounting of the ring 71 (72) on the three rollers 79a through 79c (79d through 79f) make the assembly work of the VTR very complicated.
In addition, since a burr generated on the inner peripheral portion of the ring 71 (72) during pressing of the ring 71 (72) may damage the rollers 79a through 79c (79d d through 79f) while the ring 71 (72) is rotated, burrs must be removed over substantially the entire circumference of the inner peripheral portion. However, this burr removing work is very troublesome.